The American Chestnut was one of the largest trees east of the Rockies. In this vintage photo from the American Chestnut Foundation website, note the two gentlemen standing at the trees’ bases.
American Chestnut (Castanea dentata) was once one of the most prevalent and dominant trees east of the Rocky Mountains. Its impressive size made it one of the largest eastern trees, with trunk diameters up to 10 feet or greater. Its lumber was very valuable and commonly used for furniture and fence posts. The wood is very rot resistant. Its seeds were very important to wildlife such as turkey, squirrel and deer.
In the early 1900s, an exotic fungus called Chestnut Blight was introduced to the U.S. on imported Chinese chestnut trees. Chinese chestnuts and other chestnuts from Asia have a natural resistance to the disease, however our American chestnuts do not. Chestnut Blight is an aggressive, girdling fungus which forms a canker around the trunk of the tree, blocking the natural flow of water and nutrients up and down.
Chestnut Blight spread very quickly and proved to be fatal to almost every American chestnut, effectively destroying an entire species and disrupting many unique forest ecosystems.
A very bad, mature chestnut blight canker.
Today, American Chestnuts are usually only seen in nature as suckers sprouting from stumps or unseen root systems. The suckers usually die from Chestnut Blight when they reach about 20 feet tall, while leaving the root system unharmed.
Luckily, there is a very small number of natural stands still surviving. These stands are either geographically isolated or genetically unique and possibly exhibit a natural resistance. Determining that is a difficult process involving inoculating offspring with the disease away from the natural stock to test disease resistance.
The seed of the American Chestnut was a common food of the passenger pigeon and numerous other wildlife.
I was lucky enough once to see a small, naturally occurring population of about 2,500 American Chestnuts on a dairy farm 10 miles east of LaCrosse, WI. The largest of these trees was about 50 inches in diameter, 50 feet tall and seemed to be suffering only mild damage from the Chestnut Blight infection.
There are many university research groups and private, non-profit groups dedicated to returning the American Chestnut to its original status. One such private group is the American Chestnut Foundation (www.acf.org), which is attempting to crossbreed the strongly resistant Chinese chestnut with American Chestnuts in an attempt to develop a tree which has both resistance to Chestnut Blight and the impressive growth habits of the American chestnut. I am optimistic that I will see these trees returned to the forest in some small number within my lifetime.
KEITH O’HERRIN is the City Forester for the City of LaPorte. He can be found at the Park and Recreation Office at 250 Pine Lake Ave. or reached at 326-9600.
